Begging experts to solve the problem of CSS writing blocks displayed by peers!_html/css_WEB-ITnose

The problem is as follows:
12 small DIVs are embedded in 1 large DIV. Each row is required to display 4, 2 on the left, 2 on the right, and 3 rows are displayed!
Requirement: Pure CSS without JS Code, do not use position positioning code, margin can be used, but negative values ​​cannot be used!
It is best to use FLOAT to solve the problem!
The code is as follows; it can be modified

<div style="background-color:#0066CC; width:700px; height:500px"><div style="background-color:#ff66CC; width:30px; height:30px;">  1 </div><div style="background-color:#ff66CC; width:30px; height:30px;"> 2 </div><div style="background-color:#ff66CC; width:30px; height:30px;">  3 </div><div style="background-color:#ff66CC; width:30px; height:30px;"> 4 </div><div style="background-color:#ff66CC; width:30px; height:30px;"> 5 </div><div style="background-color:#ff66CC; width:30px; height:30px;">  6 </div><div style="background-color:#ff66CC; width:30px; height:30px;"> 7</div><div style="background-color:#ff66CC; width:30px; height:30px;"> 8 </div><div style="background-color:#ff66CC; width:30px; height:30px;">  9 </div><div style="background-color:#ff66CC; width:30px; height:30px;">  10 </div><div style="background-color:#ff66CC; width:30px; height:30px;">  11</div><div style="background-color:#ff66CC; width:30px; height:30px;">  12 </div></div>

Reply to discussion (solution)

The height and width dimensions above cannot be changed!

<div style="float:left;background-color:#0066CC; width:700px; height:500px"><div style="float:left;background-color:#ff66CC; width:30px; height:30px;">  1 </div><div style="float:left;background-color:#ff66CC; width:30px; height:30px;"> 2 </div><div style="margin:0 0 0 580px;float:left;background-color:#ff66CC; width:30px; height:30px;">  3 </div><div style="float:left;background-color:#ff66CC; width:30px; height:30px;"> 4 </div><div style="float:left;background-color:#ff66CC; width:30px; height:30px;"> 5 </div><div style="float:left;background-color:#ff66CC; width:30px; height:30px;">  6 </div><div style="margin:0 0 0 580px;float:left;background-color:#ff66CC; width:30px; height:30px;"> 7</div><div style="float:left;background-color:#ff66CC; width:30px; height:30px;"> 8 </div><div style="float:left;background-color:#ff66CC; width:30px; height:30px;">  9 </div><div style="float:left;background-color:#ff66CC; width:30px; height:30px;">  10 </div><div style="margin:0 0 0 580px;float:left;background-color:#ff66CC; width:30px; height:30px;">  11</div><div style="float:left;background-color:#ff66CC; width:30px; height:30px;">  12 </div></div>

Thank you! Solve the problem !